I have some questions regarding gematria and zero:
- which characters of alphabet means zero according to gematric rules?
- since which time did Jews consider zero as a character equivalent to other alphabet characters=numbers?
- if zero appears in gematria now, but didn't at gematria's beginning, how were adapted gematria perceptions?
Could somebody point me to further reading? Because of lack of knowledge, I ask Google the wrong questions, so I can't find something substantial to read historical studies about the subject.